Internal combustion engine



April 13, 1943. 5,l A, -PYATT' 2,316,618

INTERAL COMBUSTION ENGINE Filed muy 2a, 1942 v2 sheets-sheet v1 April 13, 1943. B, A. PYATT 2,316,618

INTERNAL coMBUsTIoN ENGINE Filed July 2s, 1942r Av2 sheets-sheet 2 MM "e www Patented Apr. 13, 1943 UNITEDV STATES PATENT OFFICE Claims.

This invention relates to an internal combustion engine, and more particularly to the supplying of fuel and air to the engine to prevent the latter from failing to vdevelop a maximum amount of horse power when operating at high speed for the lack of fuel and air reaching the cylinder of the engine for ignition.

The primary object of this invention is the provision of means for permitting the exhaust valve of the engine to be employed for admitting air to the cylinder of said engine in addition to the fuel admitted by the intakevalve, when'said' engine is operating faster than a normal or predetermined speed to assure maximum horse power development by the engine, the additional amount of air as well as the amount of fuel being controllable by a means so that the speed of the engine may be varied when operating above normal or the predetermined speed, both of said means being manually controllable.

With these and other objects in View as will become more apparent vas the description proceeds, the invention consists in certain novel features of construction, combination and arrangement of parts as will be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had tothe following description and accompanying drawings, in which Figure 1 is a fragmentary vertical sectional view illustrating a portion of an internal combustion engine equipped with the present invention and showing the valve operationand flow of fuel to the cylinder under normal speed or a speed below a predetermined speed.

Figure 2 is a view similar to Figure 1 showing the fiow of fuel to the cylinder of the engine when the latter is operating at a high speed or a speed above a predetermined speed.

Figure 3 is a sectional view taken on the line 3 3 of Figure 1.v

Figure 4 is a fragmentary sectional view illustrating a means of shifting the position of the cams that operate the exhaust valve.

Figure 5 is a detail sectional view taken on the line 5 5 of Figure 4. I y

Referring in detail to the drawings, the numeral 5 indicates generally a fragmentary portion of an internal combustion engine consisting of a cylinder E, piston l, cylinder head 8 provided with intake and exhaust passages 9 and iii controlled by intake and exhaust valves I I and I2.

Connected to the intake passage 9 is a carburetor construction I3 consisting of a fuel chamber I4, an air passage I5 in the form of a manifold connected with the head 8 and including a Venturi element I6 through which air passes to the cylinder of the engine from the atmosphere, asV indicated by the arrows yin Figure 1. The fuel from the chamber I6 enters the Venturi element Iby a nozzle Il.

An exhaust manifold I8 including an exhaust pipe opening to the atmosphere is connected to the exhaust passage l@ of the head. Also connected to the exhaust manifold I8 is an air pipe is connected to the air passage I5 between its air intake and the Venturi element so that air may flow into the exhaust manifold, as shown by the arrows in Figure 2. This air may enter the cylinder by way of the exhaust valve I2 during certain operations of the engine.

The head 8 is provided with supports Z for rotatably supporting cam shafts 2l and 22. The cam of the cam shaft 2l is indicated by the character 23 for operating the intake v/alve Il in a normal four cycle manner. The cam shaft 2l is provided with a square portion on which is slidably mounted av sleeve 26 provided with cams 2a and 26. The cams 25 and 26 move with the sleeve and either may be brought into operative relation with the exhaust valve I2 for the operation thereof on a four cycle principle.

Itl is` to be noted that the cam 26 has a longer high face than the cam 25 so that the cam 25 will hold the exhaust valve I2 open longer than the cam 25.

The sleeve 245 is engaged by a fork 2l secured to an operating shaft 2d slidable in the supports 2G. Thel operating shaft 2E is adapted to slide in opposite directions for engaging and disen` gaging either the cam 25 or the cam 25 with the exhaust valve.

Connected to the operatingshaft 22 is a manually controlled operating means 30 whereby the operator may cause a force to be applied to the operating shaft 22 in either direction for the purpose of shifting the position of the cams 25 and 2S with respect to the exhaust valve when the low faces of the cams are opposite the exhaust valve. The operating means 30 may be varied as to construction and in the present showing consiste of a sleeve 3| slidably receiving one end of the operating shaft 22 which is provided with a head 32 forming a spring seat. The sleeve SI is slidably secured to the operating shaft by a head 32 having slidable engagement with the operating shaft and nxed to the sleeve 3 I.

`A spring seat 34 is formed on the sleeve and apertured to freely receive the operating shaft and has bearing thereagainst coil springs 35 and .At this operation speed, .the cam 20 operates of the spring llbean theheadll. Thus it will be seen that when theY sleeve is slid in either direction, one or the other of the springs will be placed under tension so that an endwise force, will be exerted on the operating shaft 22 suillcient to move the operating shaft to bring about sluiting of the positions of the cams 2l and 26 when the low faces are opposite the exhaust valve. Y l

Control valves 31 and Il are mounted in 4the intake and exhaust passages l and I! and include an operating arm Il to whichA are connected springs Il acting to normally position the valves 81 and It in open position; Any suitable manually operated control meansis connected to the arm I! for moving the valves 31 and I. simultaneously toward and into closed position.

The cam shafts 2i and 22 are operatively connected with the crank shaft of the engine (not shown) in any well known manner so that the engine will operate on a four cycle principle.

Stops Il are arranged on the head I of the engine to be engaged by the arm 3| to limit the movement of the control valves l1 and Il into closed position.

The carbureter intake e` 8.

lat. oneenacfi-.hsspnmumnunmtna Vheadltwhiisoneend the exhaust stroke-ofthepistonandpasstothe exhaust pipe. The rapid movement of the exhaustgases as s pecined past theinlet of the pipe il to the exhaust manifold may draw air with the exhaust gasesl to the exhaust pipe so that when exhaust valve acts to admit air tothe cylinder on the intake stroke of the piston, only air free of exhaust gases will enter the cylinder because the exhaust gases on the previous cycle has been cleared at the point of connection of the pipe I. with the exhaust manifold.

While .I have shown and described the preferred embodiment of my invention, it will be understood that minor changes in' construction, combination and arrangement of parts may be made without departing from the spirit and scope of the invention as claimed.

Having thus described` my invention, what I` claim is: l. In an internal combustion engine, a cylinder having intake and exhaust passages, a piston in said. cylinder, intake and exhaust valves I. construction Il will include -a main control valve Il operated in any suitable manner for'the control of air and y.fuel to the vIn operation, it is to be understood that the Y engine operates on the four cycle principle ,either when the engine is operating above or below normal speed or a predetermined speed. When the engine is operating at normal or below a predev iermined speed, the cam 2 5 operates the exhaust valve sothat said exhaust valve merely acts in its original capacityof scavengingthe cylinder of spentgases on the exhaust st roke of the piston.

are in open position. The fuel from the carbuieter enters the cylinder on the suction or intake stroke of the piston, 'as shown in Figure l.

' the exhaust valve is opened along with the intake.

valve il. The fuel flows into the cylinder from the carbureter as indicated by arrows in Figure 2 and also air flows into the cylinder-'by way of the the control valves 31 and 8lfor .said intake and exhaust passages, a carbureter construction connected to said intake passage for furnishing fuel and air to the cylinder under the control of the intake valve, means for operating Vsaid intake valve, and exhaust valve .operating means for operating the exhaust valve forrexhausting the cylinder of spent gases at a selectedy speed of the engine and under other selected speeds fory operating the exhaust valve to admit air to the cylinder-during the admittance vof fuel and air to said cylinder by the intake valve and to exhaust spent gases from the cylinder.

2. In an internal combustion engine, a cylinder having intake and exhaustpassages, a piston in lsaid cylinder and operating on a four cycle principle, intake and exhaust valves for said intake and exhaust passages, a carbureter construction connected to saidfintake passage for furnishing fuel and air to the cylinder under the control ofthe intake valve, a cam mechanism for operating the intake valve, and a manually shiftexhaust valve, asshown by arrows in said Figure 2. This additional supply of air to the cylinder.vl

willasaure the engine ofl operating atits maximum capacity of horpower development ata speed above normalora predetermined speed.,`

The carbureter may be provided with means (not shown) for supplying `an additional amount or .fuel into the air stream passingthrough the Ven'- furi element il' when the ,engine is operating faster than normal or a predetermined speed.V

'gine' above normal or a predetermined speed through the movement of the control valves fl and Il, the main'control valve Ii at this time or vthe predetermined speed.A It is also to be uncie'rstood'thatl when the exhaust valve is acting to admit air tothe cylinder on the suction stroke ofxthe piston, alsol actsin its normal manner-of to escape from the cylinder on the exhaust' The voperator may control the speed of the enable cam mechanism for operating the exhaust valve for .exhausting the cylinder of spent gases under 'a selected speed of the engine and under other selected speeds for 'operating Vthe exhaust valve to admit air to the cylinder during the admittance of fuel and air to said cylinder by the intake valve and to exhaust spent gases from the cylinder. l

3. In an internal combustion engine, a cylinder including` a head having intake and exhaust passages connecting with the cylinder, Vintake andsexhaust valves for said intake and exhaust es, a carbureterconstructionconnected to the intake passage for furnishing -air and fuel to the cylinder under the `control or the intake valve, an exhaust manifold connected to the exhaust vpassage and including. an vexhaust pipe yopen kto the atmosphere and a pipe connected to the ca'rbuieter construction forreceiving air rapidlyf'romthecylinderon 'is therefrom, a cam mechanism for operating the intake valve on the four cycle principle, and a cam mechanism for operating the exhaust valve on the fourcycle principle to. scavenge the cylinder of spent gases Aduring the exhaust cycle and manually shiftable to openthe exhaust valve during the admittanceof fuel and air to the cylinder by the intake valve when said engine is operating at faster than "a predetermined speed'and to open the exhanstzv'alve for scavenging the cylinder during the scavenging cycle of operation.

Y 4.-.rIn an internal combustion engine, a cylinder including a. head vhaving intake and exhaust passages connecting with `the cylinder, intake and exhaust valves for said intake and exhaust passages, a carbureter constructionvconnected to the intake passage for furnishing. air and fuel to the cylinder under the control of the intakel a four cycle principle to scavenge the cylinder v of spent gases during the exhaust cycle and manually shiftable to open the exhaust valve during the admittance of fuel and air to the cylinder by the intake valve when said engine isnoperating at speeds faster than a' predetermined speed and to open the exhaust valve for scavenging the cylinder during the scavenging cycle of operation. and simultaneously operated control valves located in the intake and exhaust passages and including spring means for normally urging said control valves into open position.

5. In mem: having intake and exhaust passages, intake and exhaust' valves vfor said-intake and exhaust passages, a 'piston operating in the cylinder on a four cyclelv principle, a carbureter construction connected to the intake passage for furnishing thelcylinder with air and fuel under the control of the 'intake valve, an exhaust manifold connected to the exhaust passage and including an exhaust pipe and an air pipe connected to the air intake of the carbureter construction, simultaneously operated control valves in the intake and exhaust passages, cam mechanism for operating the intake valve on a four cycle principle, and a manually shiftable cam mechanism including double cams for the operation of the exhaust Avalve on a four cycle principle to scavenge the cylinder of spent gases during .the cycle of exhaust for the cylinder and to open the exhaust valve during the admittance of fuel and air to the cylinder by the intake valve during predetermined speeds of operation of the engine and to allow the exhaust vvalve to scavenge the cylinder `on the scavenging stroke of the piston.

BURLEY A. PYA'I'I.l

combustion engine, a. cylinder 

